Question

  There are many interesting science experiments out there for young kids. You can surprise your friends and teachers with them. All you have to do is to put a little effort into it and you should have no problem coming up with an in?teresting science experiment. One such experiment is to show your friends and teachers that you can make mothballs (棒脑丸) dance!If you want to do it,first,be sure that you have got all the necessary sci?ence kits for your science experiment.

  What you need for this experiment is a glass filled half full with water. Add a little bit of vinegar to your glass of water,about 1/3 or 1/4 of a cup (60 ml) ,and one teaspoon (10 ml) of baking soda,and then carefully stir the mix?ture. Drop a few mothballs into the glass and have your audience watch. As long as the surfaces of the mothballs become fairly rough,they should begin to bounce up and down in the glass.

  You can also do a similar experiment with raisins (葡萄干) and clear pop,such as Sprite. In this experiment,all you have to do is to fill a glass with Sprite and drop a few raisins into it. The raisins should begin to bounce up and down in the glass of Sprite. You can also replace the raisins with mothballs and you should get the same effect in the Sprite. This project works because the irregular surfaces of the mothballs and the raisins hold some C0₂ bubbles (气泡) ，causing them to bounce up and down in a dancing motion.

1. The writer writes this passage to     .

   A. explain why some science experiments are easy

   B. encourage people to spend more time on science

   C. tell us how good he is at doing science experiments

   D. teach kids how to do an easy and interesting science experiment

2. What is the most probable name of the experiment?

   A. Producing mothballs.

   B. Dancing mothballs.

   C. Changing mothballs.

   D. Swimming mothballs.

3. Which of the following things are needed in the experiment? 

a. baking soda b. water c. mothballs

d. salt e. vinegar f. sugar

   A. beef   B. acde

   C. abed   D. abce

4. The underlined word "pop" in Paragraph 4  probably refers to a     .

   A. mothball

   B. kind of vinegar

   C. drink with bubbles

   D. special kind of raisin

5. From the last paragraph we can know .

   A. why Sprite has some C0₂ bubbles

   B. what people usually use Sprite for

   C. what scientists usually do with raisins

   D. why the mothballs bounce up and down

Answer 1

本文主要向我们介绍怎么做一个简单而又有趣的科学实验。

1. D作者意图题。通读全文可知作者主要向我们介绍怎么做一个简单而又有趣的科学实验，故选D.

2. B推理判断题。根据第一段的"One such experiment is to show your friends and teachers that you can make mothballs (樟脑丸) dance!"可知"跳舞的樟脑丸"为最佳答案。

3. D

4. C词义猜测题。根据such as Sprite以及"...hold some CO,bubbles…"可知，pop在这里是指含有二氧化碳的饮料。

5. D细节理解题。根据文章的最后一句"This project works because the irregular surfaces of the mothballs and the raisins hold some C0₂ bubbles (气泡) ,causing them to bounce up and down in a dancing motion."我们可以知道樟脑丸为什么会上下跳动。